Table 3. Mean and SD of body composition values calculated at L3 level on CT by semi-automatic and automatic segmentation, and on MRI T1-weighted and T2-weighted sequences.
| Body composition values | CT | MRI T1 | MRI T2 | |
|---|---|---|---|---|
| Semi | Auto | |||
| SMI (cm2/m2) | 46.4±13.0 | 45.2±13.5 | 44.5±11.2 | 43.11±11.24 |
| SMA (cm2) | 129.1±32.5 | 125.8±29.8 | 124.0±31.3 | 120.1±29.7 |
| SM CT density (HU) | 22.1±12.2 | 28.3±8.1 | – | – |
| SAT (cm2) | 193.6±86.8 | 186.1±99.0 | 163.5±73.6 | 160.2±73.4 |
| SAT CT density (HU) | −97.7±16.2 | −96.0±13.9 | – | – |
| VAT (cm2) | 157.0±105.9 | 150.2±105.0 | 146.5±99.1 | 161.3±105.7 |
| VAT CT density (HU) | −93.1±84.4 | −91.5±10.5 | – | – |
| (SAT + VAT)/SMI | 2.71±1.09 | 2.70±1.34 | 2.50±1.03 | 2.68±1.13 |
| SAT/VAT | 2.14±2.52 | 2.05±2.05 | 1.72±1.35 | 1.45±1.07 |
| SMI/SAT | 0.82±0.45 | 1.07±1.43 | 0.95±0.53 | 0.96±0.58 |
SD, standard deviation; L3, the third lumbar vertebra; CT, computed tomography; MRI, magnetic resonance imaging; SMI, skeletal muscle index; SMA, skeletal muscle area; SM, skeletal muscle; HU, Hounsfield units; SAT, subcutaneous adipose tissue; VAT, visceral adipose tissue.